Tristeza means 'sadness' or 'sorrow'. While it might seem like a common word, its repeated emphasis in this song makes it particularly poignant and central to the lyrics.
The song frequently mentions wanting to forget "tu amor paso las dosis de tristeza" (your love passed the doses of sadness) and "tu amor a sólo tú fuiste tristeza" (your love, only you were sadness). This repetition highlights a deep emotional struggle, making it an interesting word choice to explore the song's theme of heartbreak and the desire to overcome past sorrow.
Agua Marina's "Me Gusta Pensar En Ti" is a song about trying to forget a past love, but it's proving to be quite a challenge! The singer is surrounded by "todas las mujeres" [all the women], but it seems like no one can compare to this one person. They even mention feeling like they are who they are "porque te siento muy suave esta manera" [because I feel you so softly this way].
It sounds like this person left, only writing to say goodbye, and the singer is left with a broken heart. They're trying to drown their sorrows "entre vasos de cerveza" [between glasses of beer], hoping to "olvidar tu amor, tu pasado, triste tristeza" [forget your love, your past, sad sadness]. It's a relatable feeling of trying to move on, but that past love just keeps lingering, even through the haze of a few drinks.